In a conventional high-pressure fuel injector arrangement, a stacking arrangement is used for assembly of the injector. The parts to be assembled may include a first portion, a spacer and a nozzle assembly. The conventional injector 10, as seen in FIG. 1, includes a first portion 101 and a second portion 102. The first portion includes a piston 102, a plunger 103. The second portion 102 includes part of the first portion 101 while also containing a nozzle assembly 104. Disposed in a stack-like configuration is a spacer 105. Two pins 106, of which only one is shown, are used to align the first portion 101, the spacer 105 and the nozzle assembly 104.
The first portion 101, spacer 105 and the nozzle assembly 104 all have inlet and outlet ports or passages that must be aligned for optimum fuel metering performance. The conventional injector, therefore, relies upon positioning pins 106 for a precise alignment between these ports or passages. However, in order to form positioning holes for the pins 106, precise machining is believed to be required for these holes. Additionally, two positioning pins are required to prevent misalignment of the assembled parts. This is believed to add to the parts' cost and count during assembly of the fuel injector. Finally, the use of positioning pins and holes is believed to require at least three steps to mount the tubular members together, adding to manufacturing inefficiency.
Thus, there is a strong need to overcome these and other problems associated with the conventional fuel injector positioning assembly arrangement.